sound/pcm - Attempt to fix 'play interrupt timeout, channel dead' error

* Fix the timeout calculation to properly calculate the buffering
  timeout.

* Adjusted code taken from bug 2067 submission.

PR: 2067
msk.4: Document that MSI is turned off by default.
dhclient: Fix a busy loop

The ifi->linkstat variable seemed to be not updated after the poll
returns in dispatch.c. This might only be a hack, but it makes the
busylooping go away.